Coastal setback provisions ensure that
development is prohibited in a protected zone adjacent to the
water's edge.

A coastal development setback may be defined as a
prescribed distance to a coastal feature, such as the
line of permanent vegetation, within which all or certain
types of development are prohibited.

Coastal development setbacks have several
functions :

they provide buffer zones between
the ocean and coastal infrastructure, within which the
beach zone may expand or contract naturally, without the
need for seawalls and other structures, which may imperil
an entire beach system. Thus in this sense they may
actually reduce beach erosion.

they reduce damage to beachfront
property during high wave events, e.g. hurricanes;

they provide improved vistas and access
along the beach;

they provide privacy for the
occupiers of coastal property and also for persons
enjoying the beach as a recreational resource.

Most Caribbean Islands use the high water mark
as the baseline for measurement. For example, the planning
standards developed for the countries belonging to the
Organization of Eastern Caribbean States (OECS) (Wason &
Nurse, 1994) use it for measurement. However, there are several
problems with the use of this criterion. For instance the
position of the high tide mark varies from day to day, sometimes
its position can change by more than 10 m from one day to the
next, particularly if there is a winter swell event. It is also
somewhat subjective unless defined by an accurate vertical
height, which is not the case in the Caribbean Islands. Thus
developers and planners may differ in the interpretation of high
tide mark as a baseline.

Actual setback distances vary worldwide from 8
m in Ecuador to 1 - 3 km in Denmark (Clark, 1996). Most Caribbean
Islands have one fixed setback for all their beaches, e.g. the
setback for new development in Barbados is 30 m (100 feet) from
high tide mark, in the British Virgin Islands it is 15 m (50
feet) from high tide mark. These setback distances are rather
low, particularly if there is a major event such as a tropical
storm or hurricane.

Nevis, on the other hand has developed a
setback policy for major tourism beaches whereby a much greater
distance is left between new buildings and the high water mark.
Here all development is prohibited in the zone extending 37 m
(120 feet) from high tide mark, piled structures such as beach
bars are allowed in the zone 37 m to 91 m from high tide mark and
major hotel structures have to be 91 m (300 feet) from the high
tide mark. From a beach dynamics perspective, these setbacks are
beneficial, however, from a developer's viewpoint, these setbacks
leave a lot of valuable land tied up and unavailable for
development, and they have met with considerable resistance in
Nevis.

Wason & Nurse (1994) have suggested the
following preliminary guide to setbacks from high water for the
OECS:

These guidelines are qualified with the
statement that they are subject to studies to determine the
highest contour normally reached by high seas.

Some states in the USA utilize variable
setbacks which make allowances for natural variations in
shoreline trends from one beach to another. For instance in South
Carolina, the width of the setback is prescribed as a distance 40
times the annual erosion rate measured from the most seaward dune
(National Research Council, 1990).

Since there is a need for further development
in the coastal zone in the interests of the islands' economic
well-being, setback policies must be designed to ensure that new
development is sustainable. The concept of variable setbacks,
which make allowances for differences in the behaviour,
characteristics, erosional history and use of beaches, can best
fulfill this function in the Caribbean Islands.

However, it must be recognized that it is one
matter for planners to prescribe setbacks, but in order for them
to be successful, groups such as architects, draftsmen,
developers and the general public, must be shown the rationale
and the need for such planning tools. As with other facets of
coastal area management, the need for education, participation
and communication is of paramount importance.